Exhaust head



Dec. 8, 1953 o, MANN 2,661,964

EXHAUST HEAD Filed Dec. 15, 1950 mmnm 66:

INVENTOR /4 33 OLIVER MANN ATTOR EY Patented Dec. 8, 1953 EXHAUST HEAD Oliver Mann, Danvcrs, Mass., assignor to Sylvania Electric Products Inc., Salem, Mass., a corporation of Massachusetts Application December 13, 1950, Serial No. 200,527

1 Claim. 1

This invention relates to apparatus for the manufacture of vacuum devices and, more particularly, to a mechanism through which the exhaust tubes of these vacuum devices are connected to a vacuum pum duringtheir manufacture.

In the manufacture of vacuum devices, such as on the exhaust machine, for example, the devices, through an exhaust tube projecting therefrom, are connected to a vacuum pump for evacuation purposes. It is necessary, therefore, that this connection be made air-tight to insure satisfactory evacuation. In most cases the exhaust tube of the vacuum device projects axially therefrom and is threaded into an end of an exhaust head, fixedly mounted on the machine frame, the other end of the exhaust head being connected toa vacuum pump.

In the manufacture of circular fluorescent lamps from linear lamps, usually the linear lamps have the electrodes sealed in the ends thereof and are then fabricated to circular configuration before final evacuation and gas filling is effected. Thus the exhaust tube projecting from one end of the linear lamp must be offset a suflicient distance relative to the lamp axis to clear the other end of the lamp during the final stages offabrication to circular configuration. This requirement renders it difficult for an operator to thread the exhaust tube into an exhaust head fixedly mounted on the machine frame. The fact that the end of the lamp from which the exhaust tube extends is usually the end which is gripped by jaws Or some similar device to hold the lamp on the machine and these jaws are fixedly mounted on the machine frame adds to the difficulty because, with two fixed points, viz., the jaws for holding the lamp, and the exhaust head, the exhaust tube must be offset perfectly to avoid force fitting and excessive exhaust tube breakage. Even with perfectly offset exhaust tubes, some breakage occurs due to machine vibration.

It is, therefore, an object of my invention to provide an exhaust head, particularly adapted for use with offset exhaust tubes but not limited thereto, which avoids the difficulties mentioned above.

Another object of my invention is to insure the attainment of an air-tight seal between the exhaust tube of a vacuum device and a vacuum line.

A feature of my invention is the provision of'a "floating exhaust head which may be manipulated into position to be drawn over the free end of an exhaust tube wherever it may lie.

The exhaust head of my invention comprises a body member with an opening therein and a resilient tube disposed in this opening, the outside wall of the resilient tube and the wall of the opening inthe body member defining a chamber which is connected to a source of fluid v(gas or liquid) under pressure. 6

In a specific embodiment of my invention, the body member is provided with top and bottom cover plates, each cover plate having a tapered boss, upstanding on the inside face thereof, which fits snugly into the respective ends of the resilient tube in the body member. The bottom cover plate has an aperture therein, extending from the outside face thereof and in register with the boss on the inside face thereof, through which the exhaust tube of a vacuum device may be inserted. The top cover plate has a short metal tube upstanding on the top face thereof, in register with the boss on the inside face thereof, which is connected to a flexible vacuum hose.

A specific embodiment of my invention is shown in the accompanying drawing in which:

Figure 1 is a fragmentary plan view of a station on a rotatable turret type machine showing a specific embodiment of the exhaust head of my invention, the air line hose and. the means through which it is connected to the head being omitted for clarity of illustration.

Figure 2 is a fragmentary sectional view of Figure 1 with the exhaust head shown in section.

Figure 3 is an exploded, half-sectional, perspective view of the exhaust head.

The rotatable turret machine with which the exhaust head of my invention may be employed may be of the type shown in the co-pending application of Sandford C. Peek, J r., et al., Serial No. 200,621, filed December 13, 1950 and entitled Apparatus for Bending Linear Glass Tubing.

In this machine, the turret ring plate i has a plurality of blocks 2, one of which is illustrated in the accompanying drawing, mounted equidistant from one another about the top face thereof. A supporting web 3 is mounted on the block 2 and a lamp holder 4 is mounted on the web 3. The lamp holder 4 comprises a fixed jaw 5 attached to the top of the web 3, a movable jaw 6 pivotally mounted at 1 on the web 3, and a lever 8 pivotally mounted at 9 on the web 3 for opening and closing the movable jaw 6 with respect to the fixed jaw 5. A lamp [0 is held by the lamp holder l by closing the jaws 5 and 6 thereof about the metal cap H on the end of the lamp Ill. The lamp ID has an offset exhaust tube l2 projecting from an end thereof. 'The free end of thissexhaust tube l2 extends into an exhaust head I The exhaust head I3 comprises a body member I4 with an opening l5 therein extending from top to bottom and a resilient tube l6 disposed in the opening I5, the outside wall of the tube I6 and the wall I! of the opening I5 defining a chamber I8. The chamber I8 is connected to a source of fluid under pressure through a suitable coupling or elbow, such as. metal tube I9, which extends'through'the body'member M and into the chamber I8. The body member I4 is provided with a vent 33 which functions as a bleeder for a small current of air for cooling the chamber I8 and particularly the resilient which the flange 2I of the resilient tube I6 seats;

The bottom face of the bodytmember leispm vided with a cover plate 22. The cover plate 22 has an aperture 23 therein and a taperedboss 24 upstanding on the inside face thereof. The top f'ace of the body member. is provided with a cover plate' 25i which has attapered boss 26 on the inside face thereof andashortmetalitube 2i upstanding onthe topfacezathereof,.inmcgister with the boss 26, which is connected: tola flexible vacuum hose 28.

In assembling the exhausthead' i 3; theiresilient tubeIG is threadedintoathe opening I5rinr-the body'member l4', from1the bottom thereof, until the flange 2 I on-thesresilienttube I61 seats on the shoulder "in the body member I l; The bottom cover plate 22nis1 positioned by inserting: the tapered 'bosszflaupstanding thereoniinto the bore of 'the resilient tube. I fil-untilzthe inside faceof the cover plate 22' engages: theadjacent. face of the body member Ill; The: cover-plate .22 is. then attached to the:..bodymember: I4; such as by screws 29afor example; Theztopfcoverplate is then positionedby inserting the tapered; boss 2'6 upstanding: thereon: intoth'e bore of. the resilient tube Ifiiuntil the; inside face .of: the: cover plate :25v engages; theiadjacentlface of the body member III; The cover-Jplate 25tisthenrattached tothe body'member: l4,-: such; as: by'screws- 30 for" example.

:After therexhausthea'dz I3 has been assembled it is connected tor-theapparatus"withvwhichitis employed. The free'end ofra flexible .hose -3I, connected tora source: of fiuidundergpressure, such as "airzf or example, .is r drawn-l down over. the metal tube I9 which:extendsiintosthe chamber I8 in theexhaust head: body, member: I 4 therebyconnectingthe chamber IBtoasource-of air under pressure.

The free end of theflexible' vacuum hose28; which extends through a .guide bracket 32 mounted on the blocki2 onthe turret ring;.plate I,,is drawn'downover the :metal tube2'i,:.ithereby connecting; the bore of the resilient tube; therethrough to a vacuum pump; (notrshown).

In positioning I a-zlamp I0 on themachine, the metal'cap II on therendthereofiswplaced between the jaws: 5 and S and: the? j awsvare. closed by movementof; thelever. 8-.- The" exhaust head I3, which.has-considerable freedom of move!- mentsince-it is mounted on anlendi ofifiexi-ble 11058128; is then manipulated intopositionso that theaperture 23 in the bottom thereof .isinregis ter with .the free: end of the :exhaust tube I 2 and the exhaust head is vthen idrawn down oven the exhausttube I2 untilrthe exhaustttube; I2 extends a considerable distance into. the. bore .of the resilient-.-tube I16;

With the lamp l0 thusly connected to the ex haust head I3, air under pressure is introduced into the chamber l8 through hose 3| and metal tube I9, thereby causing sufiicient deformation of the resilient tube IE to effect an air-tight seal between the resilient tube l6 and the lamp exhaust tube I2 which lies in the bore thereof. Preventionro'fair leakageat thewen'ds of the resilient tubelE-is assured" by the force fitting of the tapered bosses 24 and 26 into the bore at the ends thereof. The provision of a shoulder 2'0=-on-:which the flange 2| of the resilient tube I6 seats further insures an air tight seal because it avoids excessive deformation of the resilient 'tubevlli'wliich might occur when the tapered boss ZTis'fOrce-fittedintO the bore thereof, and prevents this -endl-of th e tube I6 from being pushed up into the opening I5 in the body member I4.

Although in the description of the specific embodiment of my invention illustrated in the drawing, the fluid pressure medium is identified as air, a liquid fluid may also be employed=w-ithout departing from the spirit of my invention 'Wh'atI' claim is:

An exhaust headeomprising: a body member having an opening: therein extending from 'top to bottom thereof, the bottom 'face'of. said body member having aicounterbore defining a shoulder therein surrounding the opening, the.- op'ening in the upper faee being eylindrioa'ka resilient tube h'avinga bore-initially of uniformrcross section throughout. its length disposed insaid openin'g and extending from .top: to bottom thereof, said resllientatube having a flange 'formedon-one end thereof, the opposite end of said 'tube being eylindric'al to fit within' the cylindrical opening in the upper face, said flange seating on s'a'id shoulder, theoutside .Wall of -sai'd resilient tube and the wall of=the opening in the'body-member defining-achamber in) the body member-pa rigid tube connected to a side of said 'body 'memberrthe bore thereof' being in communication with the chamber in the body: member, a cover plateattached to the bottom face of said body member and comprising means. to clamp" said 'fiange againstsa'id shoulder-,said cover .pla't'e having an inwardly taperedaperture therein and a hol low externally tapered boss upstanding on the insideface: thereof extending into the bore of said resiiient-tuba said boss being: in register with said aperture; an'da second' cover plate attached to thetbpface' of said body memberpsaid' se'con'd cover plate having an externally tapered boss with a bore therethrough, said boss upstanding on= the'inside face thereof extending into the bore of saidresilient tube,- and a-rigid tube upstanding on the I outside face thereof adapted. to be inserted'within a resilient tube,- the bore of saidrigid tube beingain register. with the bore of said. tapered boss.

OLIVER? MANN-:1

References Gited in the file of this pa'tent .LJNI'II-lillii' STATES PATENTS Number Name Date:

3179108 Moeser ,May; 5', ,11885 136L726" Trout: 1June:7;. 1932 :2;465,'843 .Gollins aet -al. Mar-.i-29;=,19,49 2,523;7l6 Parr -1 Sept. 26,11,950 

